1. Field of the Invention
The present invention relates to a system for delivering interactive information services, such as video, audio, library, interactive games, and the like to one or more subscribers. More particularly, the invention relates to a system for establishing a multi-channel communicative connection between a subscriber's set top terminal and a service provider and then managing the communications necessary to deliver interactive information services to the subscriber(s).
2. Description of the Background Art
Recent advances in digital signal processing techniques and, in particular, advancements in digital compression techniques, have led to a plethora of proposals for providing new digital services to a subscriber's home via existing telephone and coaxial cable networks. For example, it has been proposed to provide hundreds of cable television channels to subscribers by compressing digital video, transmitting the compressed digital video over conventional coaxial cable television cables, and then decompressing the video at the subscriber's set top terminal. Another proposed application of this technology is a movie-on-demand video system in which a subscriber communicates directly with a video service provider via telephone lines to request a particular video program from a video library and the requested video program is routed to the subscriber's home via telephone lines or via the coaxial television cables for immediate viewing.
However, these present movie-on-demand video systems are not truly interactive systems wherein a subscriber can selectively access a large audio, video or data library and control the presentation of the selected information on a real-time basis, as when a video program is played using a video cassette recorder (VCR). Most of the presently available systems have a simple control interface that permits subscribers to merely order information without any further control of the presentation of the information. Other, more sophisticated systems, have a control interface that contains more complex commands such as start, stop, pause, fast-forward and rewind to permit rudimentary control of the presentation of the information. However, these systems use conventional signaling and information routing networks that are relatively slow to react to the commands, e.g., the latency between the instant an interactive function is requested and when that function takes effect is extremely long. Furthermore, the set top terminals used by these systems contain complex and costly electronics to facilitate processing of the complex commands. Additionally, these systems use a conventional cable television network architecture, where a central data server transmits data to a plurality of head end subsystems which in turn propagate various subsets of the data to an individual or a multiplicity of set top terminals. The servers in such systems perform much of the control functions and, as such, the latency arising from sending control commands through the head end to the server is substantial.
Therefore, there is a need in the art for a cost effective, interactive information distribution system that provides real-time interaction (with relatively short latency) between the subscriber and the service provider at any time during the presentation of requested information.